What are microbicides and why are they important?
The word microbicides (My-crow’-bus-ides); refers to a new type of product being developed that people could use vaginally or rectally to protect themselves from HIV and possibly other sexually transmitted infections. A microbicide could be produced in many forms, including gels, creams, suppositories, films, or as a sponge or ring that releases the active ingredient over time. Microbicides would be the most important innovation in reproductive health since the Pill.
Where can we get microbicides?
Scientists are currently testing many substances to see whether they help protect against HIV and/or other STIs, but no safe and effective microbicide is currently available to the public. However, scientists are seriously pursuing more than 50 product leads, including about a dozen that have proven safe and effective in animals and are now being tested in people.
It is impossible to say how long it will take to find a microbicide that is both safe and effective. On average, new drug development takes over a decade from discovery in a research lab to availability on the market. Ninety percent of candidates that enter preclinical testing are rejected before they enter clinical trials. Only a few microbicide candidates are in the last stages of testing to determine whether they are effective (which can take up to 4 years). We do not know yet whether these candidates will work.
If a trial shows that a microbicide does work, at least another two to four years will be required for individual countries to go through their own regulatory and manufacturing processes to make the microbicide available. Due to these individual country processes, it must be noted that a microbicide will not be available in all countries at the same time and not all people within a country will get it at the same time. It is likely to be made available to some women and not others during introduction and scale-up.If the current set of products in effectiveness trials does not prove effective, this time horizon will be longer. There are several candidates already in clinical safety testing and in pre-clinical laboratory testing. The field needs to ensure that the entire research pipeline continues to advance.
Why are microbicides needed?
Today’s prevention options –condoms, mutual monogamy, and STI treatment– are not feasible for millions of people around the world, especially women. Many women do not have the social or economic power necessary to insist on condom use and fidelity or to abandon partnerships that put them at risk. Because microbicides would not require a partner’s cooperation, they would put the power to protect into women’s hands.
Why are microbicides not yet available?
Investment in microbicide R&D must expand dramatically –and quickly– if the promise of microbicides is to be realised. In the short term, funding must come from the “public sector” –governments and philanthropic donors– because it is not in the economic self-interest of pharmaceutical companies to fill this R&D gap.
Isn’t it expensive to develop this kind of product?
Yes, however, it is essential that microbicides get into the hands of women and men who need them at a price they can afford. In the past, new health technologies have rarely become widely available in developing countries until more than a decade after their approval in the US and Europe, an unacceptable delay for this life-saving technology developed primarily with public funds. Advocates are working with researchers and policy makers to emphasise the need to address issues of access and affordability up front, in order to deliver a microbicide rapidly once it is proven safe and effective.